Magnetic field ($\overrightarrow{\mathbf{B}}$)

The magnetic field contributes the velocity-dependent term $qv\times B$ to the Lorentz force.

A magnetic field is a region around a magnetic material or a moving electric charge within which the force of magnetism acts. It is represented by magnetic field lines that indicate the direction and strength of the magnetic force. The magnetic field can affect other charged particles and materials, resulting in forces that can cause motion or alignment, as experienced with magnets.